THE SAND-LOVING AMMOPHILA 225 



with the illustration in Holland's Moth Book of Lycia cog- 

 nataria, Guenee. This is a Geometric! that is known to be 

 protectively colored and stiffens out to resemble a dead twig 

 when attacked, yet somehow pictipennis gets it. Another 

 Lepidopterous larva used by this wasp is Prodenia ornitho- 

 galli Guen. [S. B. Fracker]. One green caterpillar of the 

 Noctuidae [S. B. Fracker], taken from pictipennis while in 

 transportation, lived eight days. 



The impression exists that the cut-worms used by Animo- 

 phila are subterranean caterpillars. Kellogg says : 5 "Almost 

 all cut-worms hide in cracks in the ground by day, feeding 

 during the night," and, since cut-worms are so often used 

 by pictipennis, it would seem that she would be obliged to 

 acquire the subterranean hunting habits of her European 

 cousins. In fact, Turner 6 describes the behavior of an 

 American Ammophila sp. that digs in the ground for cater- 

 pillars with which to stock the nest. This leads him to con- 

 clude that "some of our American Ammophilas resemble 

 those studied by Fabre in storing their nests with subter- 

 ranean caterpillars." 



We have never been so fortunate as to observe these 

 wasps at the moment of capture of the prey, but, on one 

 occasion, we saw one whose behavior was such as might 

 easily arouse suspicion. This insect was running about 

 a small plot of ground, in so strange a manner that our 

 .interest was at once attracted. It would take short flights 

 in the air just above the ground and suddenly drop to the 

 ground, with a sort of thump, landing on all its legs as if 

 sounding the earth. Here it would walk slowly about the 

 spot for a few seconds, then wheel round in another short 

 flight and repeat the performance. This it continued to do 

 for twenty minutes, until at length it seemed to decide upon 



5 Am. Insects, p. 402. 1905. 



6 Psyche 18: 14. 1911. 



